I. Field of the Invention
This invention relates to packaging for shipping containers and more particularly to dunnage used in packing shipping containers which dunnage is likely to be thrown into the environment once it is no longer used for packing.
II. Discussion of line
The packing and shipping of articles, particularly fragile articles, has always presented certain difficulties, including the danger of breaking, scrapping, chipping or otherwise damaging the articles. Accordingly, materials are used to support and cushion articles being shipped in order to prevent damage. For example, U.S. Pat. No. 2,281,657 discloses a package that protects flat articles against abrasion by firmly holding the articles in the package so that no rubbing takes place. As another example, U.S. Pat. No. 2,005,967 discloses a package In which an article is immobilized by use of corrugated cardboard and filler material. In yet another example, U.S. Pat. No. 3,356,209 discloses foam plastic to immobilize and cushion the article.
Such packaging with use of fillers has been successful in preventing breakage, but not without a cost in other ways. Often when shipped articles are unpacked and the packaging is discarded, and the fillers are thrown out into the environment, producing costs in cleaning up the environment, producing landfills, and operating incinerator systems with complex filtration methods for reducing effluent emissions.
There are those skilled in the art who have become particularly aware of environmental concerns, and have reduced the assaults on the environment by recycling dunnage. But recycling causes other problems. One problem is that composite dunnage, such as foam products attached to corrugated fiberboard sheets or plastic products of different chemical makeup, requires that the constituent parts that are not chemically the same to be separated for different recycling treatments. Inasmuch as composite products are usually attached together by use of adhesives or stapling items, such constituent parts are hard to separate as chemically different parts. Accordingly, often composite items that are not separable from other recyclable items are destroyed by methods having the environmental consequences sought to be avoided.
III. Prior Art
Conventionally, two-piece composite dunnage is structured as the example of the prior art shown in FIG. 1 of the drawings. A composite dunnage section 100 comprises a foam or cushioning product 110 attached to a corrugated product 112. The foam product 110 is attached to the corrugated product 112 by an adhesive 114 applied to the foam product 110, the corrugated product 112, or both.
A device for separating articles packed in a container, improved from the standpoint of being kinder to the environment, was developed by the inventors. The device is composite dunnage 200 comprising a foam or cushioning piece 210 mechanically attached to a plastic corrugated sheet 212. The cushioning piece 210 includes a plurality foam cushioning sections 214 joined by and projecting from an integral foam web 216. The foam cushioning sections 214 project from the foam web 216 into a cross-section of a varying width. The plastic corrugated sheet 212 to which the foam piece 210 is Joined has a plurality of openings 218 therein, each of a width adapted to accept a foam cushioning section 214 when the foam cushioning section 214 is compressed to be forced through the opening 218 in the plastic corrugated sheet 212. Once forced through and allowed to decompress, at least one cross-sectional portion of each of the foam cushioning sections 214 decompresses to a width that is greater than the width of the corresponding opening 218 in the plastic corrugated sheet 212, thus impeding the foam cushioning section 214 of the foam piece 210 from passing back through the corresponding opening 218. The common Joining foam web 216 remains on a side of the plastic corrugated sheet 212 opposite the side trapping the decompressed foam cushioning sections 214, so that the plastic corrugated sheet 212 is trapped between the foam web 216 and the greater width portions of the foam cushioning sections 214. This mechanical attachment allows the composite dunnage 200 to be reused. When the composite dunnage 200 is no longer needed, each foam cushioning section 214 may again be compressed to be pushed through each opening 218, thereby separating the foam piece 210 from the plastic corrugated sheet 212 without any adhesive residue.
While the foregoing product provides for a solution in separating different parts of the dunnage, the product is not particularly adapted for the packing of large articles in a shipping container. One shortcoming of our earlier invention is that the disposition of the web on the opposite side of the sheet from the foam cushioning sections is wasteful in most applications, particularly where the shock absorbing characteristics of the foam piece is more advantageous when fully used in contact with an article shipped. Another shortcoming is that tapes, adhesives and staples are often necessary to position the product at an elevation at which a shipped article might come into contact with a side of a shipping container.